Blow-out preventer



Dec. 15, 1936. J. D. NlxoN 2,064,267

Y l'BLOW-OUT PREVENTER 4 Original Filed March 14, 1952 3 Sheets-Sheet lM fw Dec. l5, 1936. `J D, NlxoN 2,064,26'?

BLOW-OUT PREVENTER Original Filed March 14, 1932 .SSheets-Shee 2 Dec.15, 1936. J, D, NIXON 2,064,267

BLOW-OUT PREVENTER Original Filed March 14, 1932 3 Sheets-Sheet 3Patented Dec. 15, 1936 UNITED STATES PATENT OFFICE 598,848, March 14,

1932-. This application March 14, 1935, Serial No. 11,178

9 Claims.

This invention vrelates to a blowout preventer.

An object of the invention is to providean apparatus to be installed onan oiiter pipe, or casing, in a well for thepurpose of controlling orpreventing the escape of fluid, under pressure, from the well betweenthe outer pipe and an inner pipe therein. The invention embodies novelmeans for forming a close seal about said inner pipe and for completelyclosing the space between said pipes whereby the escape of fluid, underpressure, from the well, through said space, may be entirely prevented.

Another object is to provide apparatus of the character describedembodying oppositely arranged guide cylinders and rams or plungerstherein, normally retracted when in inactive position so as not tointerfere with operations in the well, said apparatus being equippedwith means for quickly moving the plungers into active position, when ablowout is threatened, so as to completely close the space between saidpipes; and the invention also comprehends plungers of such novelconstruction as to not only for-m said close seal about the inner pipe,when the plungers are in active position, but also to form leak proofjoints with their respective cylinders when subjected to the internalpressure of the well. l Another object of the invention is to provide,'in apparatus of the character specified, plungers of such constructionthat they may be moved into position to form a close seal about theinner pipe with a minimum of friction withthe cylinder walls, and which,upon further movement of said plungers, will form also close sealsbetween the respective plungers and the walls of the correspondingcylinders.

A further object is to provide a novel type of ram, or plunger havingits forward end formed to fit closely about-said inner pipe and composedof resilient material anchored in place by a rigid cage-like structureso shaped that said inner end of the plunger will be positivelymaintained in close ttlng contact with the inner pipe under any wellpressure to which it may be subjected.

With the above and other objects in view, as will be more specificallyset forth hereinafter. this invention has particular relation to certainnovel features of construction, operation and arrangement of parts anexample of which is given in this specification and illustrated in theaccompanying drawings, wherein:-

Figure 1 shows a side view of the apparatus, partly in section.

Figure 2 shows a plan view thereof, partly in section.

Figure 3 shows a plan view of the ram, or plunger, partly in section.

Figure 4 shows a side elevation thereof, partly in section.

Figure 5 shows an enlarged, fragmentary longitudinal sectional view ofthe cylinder and the plunger actuating means associated therewith, and

Figure 6 shows an inner end view of the plunger cage. l

Referring now more particularly to the drawings, wherein like numeralsof reference designate similar parts in each of the views the numeralsl, l designate opposing cylinders which are preferably joined integrallytogether. Fastened on the outer ends' of these cylinders are therespective heads 2, 2. Approximately midway between the heads, thecylinders have the depending tubular connection 3 for attaching theapparatus to the casing t in the well, and said cylinders also havingthe upstanding, tubular connection 5, opposite the connection 3 wherebya Christmas tree or other desired equip--- ment may be installed inplace. Above the casing li there are the outlet connections 6, d for theattachment of flow lines to the apparatus.

Suitable means for operating the device will be employed: Asillustrated, said operating means includes the axial shafts l,y 'lhaving swivelling connections with, but confined against longitudinalmovement relative to the heads 2 and fixed on the outer ends of theseshafts are the gears 8, 8. 'I'here is a countershaft 9 rotatable insuitable bearings in the heads 2 and which has the pinions l0, l0 fixedthereon and in mesh with the respective gears 8 whereby they shafts 'lmay be turned. The shaft 9 may be driven in any selected manner, as by ahand 40 wheel ll, xed thereon. The inner ends ofthe shafts 'l areprovidedA with external coarse threads which are reversely pitched andin mesh with the internal coarse threads of the sleeves l2, l2 securedin the outer ends of the plungers, 45 hereinafter described. By rotatingthe shaft 9 in one direction the plungers may be simultaneusly movedinwardly and closed about an inner pipe i3 in the well and the spacebetween the outer pipe, or casing ll, and the inner pipe i3 closed; andby rotating the shaft 9 in the other direction the plungers be movedoutwardly into inactive position so as not to interfere with operationsin the well.

The rams, or plungers, hereinabove referred to work in the respectivecylinders I, l and' are of special construction and will now bedescribed:- l

Each plunger is formed with a body Il shaped tovt in its correspondingcylinder I and a cage, or skeleton I5. As shown, the outer end. of eachcage is reduced and telescoped within the adiacent end ofthecorresponding body I 4. 'Ihe reduced end of each cage is pr'ovided witha socket I6 to receive a strong coil spring I1 interposed between saidcage and the opposing en d of the corresponding sleeve I2. The body I4and cage I5 may be retained in assembled relation by the pin I6 whichhas a threaded connection with the body Il and whose inner end projectsinto a longitudinal, external, slot I9 in the corresponding cage I5.'I'he body and cage of each plunger thus have a limited lengthwisemovement relative to each other.

The inner, or forward, end of each body I is approximately wedge-shaped,thus forming prongs 20, 20 which embrace the corresponding cage onopposite sides and these prongs have the arcuate, outwardly andforwardly pitched end faces 2|, 2|. These faces are opposed by thecorrespondingly shaped and pitched faces 22, 22 of the correspondingcage, said faces 22 being formed by the reduction of the outer end ofsaid cage. The faces 22 are approximately parallel with and are spacedfrom the opposing faces 2|, thus providing the upper and lower arcuateexternall grooves in each plunger which merge, on opposite sides, at theforward end of the cage. Leading from these respective upper and lowergrooves through the cage are the channels 23, 23 whose forward ends areflared, as at 2li, and terminate in the forward face of the cage.

In horizontal contour the inner end of each cage is approximatelyarcuate to conform to the contour of the inner pipe and is faced withrubber, or other selected resilient material 25. 'I'his material ismoulded in place and similar material 26 is moulded into the upper andlower grooves of the plunger and tied to the facing 25 by the ties 2l ofsimilar material in the channels 23. These resilient parts are allmoulded in place about the cage at one moulding operation..

The adjacent ends of the cages I5, above and below are similarlyattened, as at 28, 28, and between the flattened faces, thus formed, andthe channels 23, are the upper and lower, horizontal grooves 29, 29whose ends taper out and are inwardly turned as more clearly shown inFig. 6.

Between the ared ends of the channels 23 on the forward arcuate face ofeach cage there is a transverse arcuate, rib 30, convex in verticalsectional contour, and between the grooves 29 and the adjacent channels23 the said forward face of each cage has the vtransverse arcuate ribs3|, 3|, convex in vertical cross sectional contour, all as more clearlyshown in Figures 4 and 6 to the end `that the forward arcuate faces ofthe cages will be in effect, transversely corrugated, and the resilientmaterial 25 will be moulded about said corrugations.

As shown in Figures 1 and 2 each resilient facing 25 recedes, or tapers,from the horizontal central line thereof to the end that when theplungers are moved inwardly into active, -or closed, position about theinner pipe the elevated portion of the resilient material on theforilvard.

end of each plunger will rst contact with said inner pipe and as theplungers are moved on to final closed position the resilient material ofsaid forward ends will be crowded each way and into the corrugations ofthe cage and will thus be -held firmly in position against the wellpressure to which it may be subjected.

The springs I'I are of suillcient strength to withstand the stressrequired to force .the plungers into closed position about the innerpipe without subjecting the resilient rings 26 in the plunger grooves toany considerable compression so that there will be no considerablefriction between the plungers and the walls of the cylinder as saidplungers are moved to closed position. Further inward movement of theplunger bodies I4 will result only in the compression of the springs I'Iand of the resilient rings 26 and these rings will thereupon be expandedout into rm contact' with the cylinder walls entirely around the lowerand upper connections 3 and 5. On account of the pitch of the faces 2|,o22, these rings assume an inwardly open, cup-shaped contour, having theoverhanging lips, as 32 which overhang the outwardly beveled portions33, at the outer margins of the faces 22, thus leaving annular spacesunderneath said lips which the pressure fluid, escaping past the cages,may enter to hold said lips closely against the cylinder walls toprevent the escape of the fluid past the plungers.

In the outer ends of the bearingsof the shafts 'I in the heads 2 are theannular, inwardly tapering seal rings, as 34, formed of lead or othersuitable material and the outer ends of the hubs of the gears 8 have theannular ribs 35. When it is desired to close the blow out preventer andto maintain the well under pressure for a considerable period of time,the gears 8 may be reversed, as shown in Figure 5, and the retainingnuts 36 screwed up tight to forceY the ribs 35 against said seal rings34 which in turn will be forced inwardly to lclosely surround the shaftsl. The equipment attached to the "connection 6 may then be closed andthe well may be maintained under pressure for an indefinite length oftime even though the resilient material 25, 26 should deteriorate topermit the escape of pressure past the plungers.

Each head 2 has a relief channel 31 which communicates with thecorresponding cylinder and which is normally open to permit the freeinlet and outlet of air during the operation of the correspondingplunger, and to permit the drainage of any water that may collect insaid cylinder.

When the blow out preventer is to remain closed to maintain the wellpressure for any considerable length of time these relief channels maybe closed, as by means of plugs 38 screwed into the outer ends thereof.

The drawings and description disclose what is now considered to be apreferred form of the invention by way of illustration only, while thebroad principle of the invention will be defined by the appended claims.y,

What I claim is:

1. Apparatus for controlling the flow of` fluid, under pressure, from awell, comprising cylinders, means for connecting said cylinders to anouter pipe in the well, said apparatus having an opening for an innerpipe within and spaced from'the outer pipe, plungers in the cylinderseach having relatively movable parts and a yieldable member between saidparts, means for moving the plungers into inactive position to clear thespace between the pipes and into active position about said inner pipeto close said space, said yieldable member maintaining the correspondingplunger parts against relative movement as the plunger is moved to saidactive position and thereafter yielding to .permit relative movement ofsaid parts, and resilient means arranged to be expanded upon saidrelative movement to form a close iit, with the corresponding cylinderwall, around said plunger.

2. Apparatus for closing the space between an outer pipe and an innerpipe in a well, comprising cylinders attached to the outer pipe,plungers in the cylinders movable into inactive position to clear saidspace and into active position to close said space, the forward ends ofsaid plungers having resilient material thereon shaped to fit about theinner ypipe when the plungers are in said active position, each plungerhaving an outer body and an inner cage and a yieldable memberbetweensaid body and cage and also having expansible means disposed betweenopposing parts of the body and cage arranged to be expanded uponmovement oi said plunger to active position to form a close fit with thecorresponding cylinder wall around said plunger.

3. Apparatus for closing the space between an outer pipe and an innerpipe in a well, comprising cylinders attached to the outer pipe,plungers in the cylinders movable into inactive position to clear saidspace and into active position to close said space, the forward ends ofsaid plungers having resilient material thereon shaped to fitabout theinner pipe when the plungers are in said active position, each plungerhaving an outer body and an inner cage and a yieldable member betweensaid body and cage and also having expansible means disposed betweenopposing parts ofthe body and cage arranged to be expanded upon movementof said plunger to active position to form a close fit with thecorresponding cylinder wall around said plunger, and tie members througheach cage connecting the resilient forward end of the plunger to-saidexpansible means on opposite sides of the plunger.

4i. .d blow out preventer having an opening therethrough and comprisingcylinders, plungers therein whose inner, or forward, ends are shaped tont around a pipe through said opening, means for moving the plungersforwardly, into position to surround the pipe, and outwardly intoretracted position, each plunger having a resilient forward end face andresilient external annularpacking members and relatively movable partsconilning said members, means between said relatively movable partsnormally preventing the relative movement thereof, said means beingyieldable to permit such relative movement at the limit of the forwardmovement of the' plunger whereby said members are caused t'o expandagainst the plunger wall entirely around the plunger.

5. In a blow out preventer a plunger including a body, a cage, ayieldable member between the body and cage, said body, and cage, havingexternal, spaced, abutments therearound forming a seat between them andresilient material seated in said seat and expansible outwardly upon therelative movement of said abutments tovmrd each other.

6. In a blow out preventer a plunger having a relatively movable bodyand cage and a yieldable member between them, an external resilient ringbetween the body and cage arranged to be compressed, and expandedoutwardly, by them, the forward end of the cage being approximatelyarcuate in horizontal cross sectional contour, said end having acorrespondingly shaped, resilient facing thereon.

7. In a blow out preventer a plunger having a relatively movable bodyand cage and a yieldable member between them, an external resilient ringbetween the body and cage arranged to be compressed, and expandedoutwardly, by them, the forward end of the cage being approximately:arcuate in horizontal cross sectional contour, said end having acorrespondingly shaped, resilient facing thereon, united to said ring.

8. A blow out preventer having an opening therethrough and comprisingcylinders, plungers therein whose forward ends are shaped to fit arounda pipe through said opening, means for moving the plungers forwardlyinto position to surround the pipe and outwardly into retractedposition, each plunger having external resilient means shaped tosurround said plunger and also to complement each other to completelysurround said opening when the plungers are in their forgated andresilient material covering said corrugated end of the plunger.

. JEDDY D. NIXON.

